Mercurial > hg
view hgdemandimport/__init__.py @ 39814:d059cb669632
wireprotov2: allow multiple fields to follow revision maps
The *data wire protocol commands emit a series of CBOR values.
Because revision/delta data may be large, their data is emitted
outside the map as a top-level bytestring value.
Before this commit, we'd emit a single optional bytestring
value after the revision descriptor map. This got the job done.
But it was limiting in that we could only send a single field.
And, it required the consumer to know that the presence of a
key in the map implied the existence of a following bytestring
value.
This commit changes the encoding strategy so top-level bytestring
values in the stream are explicitly denoted in a "fieldsfollowing"
key. This key contains an array defining what fields that follow
and the expected size of each field.
By defining things this way, we can easily send N bytestring
values without any ambiguity about their order. In addition,
clients only need to know how to parse ``fieldsfollowing`` to
know if extra values are present.
Because this breaks backwards compatibility, we've bumped the version
number of the wire protocol version 2 API endpoint.
Differential Revision: https://phab.mercurial-scm.org/D4620
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 20 Sep 2018 12:57:23 -0700 |
parents | 670eb4fa1b86 |
children | 2372284d9457 |
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# hgdemandimport - global demand-loading of modules for Mercurial # # Copyright 2017 Facebook Inc. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. '''demandimport - automatic demand-loading of modules''' # This is in a separate package from mercurial because in Python 3, # demand loading is per-package. Keeping demandimport in the mercurial package # would disable demand loading for any modules in mercurial. from __future__ import absolute_import import os import sys if sys.version_info[0] >= 3: from . import demandimportpy3 as demandimport else: from . import demandimportpy2 as demandimport # Full module names which can't be lazy imported. # Extensions can add to this set. IGNORES = { '__future__', '_hashlib', # ImportError during pkg_resources/__init__.py:fixup_namespace_package '_imp', '_xmlplus', 'fcntl', 'nt', # pathlib2 tests the existence of built-in 'nt' module 'win32com.gen_py', 'win32com.shell', # 'appdirs' tries to import win32com.shell '_winreg', # 2.7 mimetypes needs immediate ImportError 'pythoncom', # imported by tarfile, not available under Windows 'pwd', 'grp', # imported by profile, itself imported by hotshot.stats, # not available under Windows 'resource', # this trips up many extension authors 'gtk', # setuptools' pkg_resources.py expects "from __main__ import x" to # raise ImportError if x not defined '__main__', '_ssl', # conditional imports in the stdlib, issue1964 '_sre', # issue4920 'rfc822', 'mimetools', 'sqlalchemy.events', # has import-time side effects (issue5085) # setuptools 8 expects this module to explode early when not on windows 'distutils.msvc9compiler', '__builtin__', 'builtins', 'urwid.command_map', # for pudb } _pypy = '__pypy__' in sys.builtin_module_names if _pypy: # _ctypes.pointer is shadowed by "from ... import pointer" (PyPy 5) IGNORES.add('_ctypes.pointer') demandimport.init(IGNORES) # Re-export. isenabled = demandimport.isenabled disable = demandimport.disable deactivated = demandimport.deactivated def enable(): # chg pre-imports modules so do not enable demandimport for it if ('CHGINTERNALMARK' not in os.environ and os.environ.get('HGDEMANDIMPORT') != 'disable'): demandimport.enable()